The Hertz contact stress usually refers to the stress close to the area of contact between two spheres of different radii. After Hertz’s work, people do a lot of study on the stresses arising from the contact between two elastic bodies.
- 1 What is Hertz theory?
- 2 How do you calculate contact pressure?
- 3 What is the basic difference between the Hertz and JKR contact models?
- 4 What is contact stress?
- 5 What is a bearing stress?
- 6 What is Hertz definition?
- 7 What is Hertzian contact?
- 8 What is an elastic half space?
- 9 What is mechanical contact stress?
- 10 Which of the following is an example of contact stress?
- 11 When there is no relative motion between two machine parts Localised Compresive stress developed at the surface of contact is known as?
What is Hertz theory?
Hertz theory assumes that surfaces are continuous and nonconforming, strains are small, each solid can be considered as an elastic half-space, and surfaces are frictionless. Under these assumptions, only normal pressure acts between two bodies due to Hertz contact producing normal displacements of the surfaces.
How do you calculate contact pressure?
In a rectangular section ring, the mean specific contact pressure P (MPa) is calculated; P = E (m1 – s1)/d1/(7.07(d1/a1 – 1)3), where E (MPa) is the Young’s Modulus and the dimension of every part is given in mm.
What is the basic difference between the Hertz and JKR contact models?
The Hertz model does not consider the adhesion in contact. The JKR model includes only a short-range adhesion in the contact area, actually it is a ± function with the work of adhesion 1° . The DMT model shows a long- range surface force which acts outside the radius of the circle of contact.
What is contact stress?
Description. Contact stress happens when force is concentrated on a small area of the body, pinching or crushing tissue and causing discomfort and often pain. You experience contact stress, for example, when the edge of a work surface digs into your forearm or wrist.
What is a bearing stress?
Bearing stress is the contact pressure between the separate bodies. It differs from compressive stress, as it is an internal stress caused by compressive forces.
What is Hertz definition?
The number of hertz (abbreviated Hz) equals the number of cycles per second. The frequency of any phenomenon with regular periodic variations can be expressed in hertz, but the term is used most frequently in connection with alternating electric currents, electromagnetic waves (light, radar, etc.), and sound.
What is Hertzian contact?
Contact mechanics is part of mechanical engineering. … Hertzian contact stress refers to the localized stresses that develop as two curved surfaces come in contact and deform slightly under the imposed loads. This amount of deformation is dependent on the modulus of elasticity of the material in contact.
What is an elastic half space?
The theory of continuous elastic half-space implies that the subgrade forms a continuous, homogeneous and perfectly elastic body of infinitely large size, limited from above by the plane on which lies the foundation structure. Sometimes it is referred to as the Boussinesque model of soil.
What is mechanical contact stress?
Mechanical contact stress The contact of the body with a hard surface or edge that results in the compression of tissue. Can also result when using a part of the body as a hammer or striking instrument.
Which of the following is an example of contact stress?
Examples of contact stress include resting wrists on the sharp edge of a desk or workstation while performing tasks, pressing of tool handles into the palms, especially when they cannot be put down, tasks that require hand hammering, and sitting without adequate space for the knees.
When there is no relative motion between two machine parts Localised Compresive stress developed at the surface of contact is known as?
Crushing Stress (Bearing Stress) • A localized compressive stress at the area of contact between two components having no relative motion between them is known as crushing stress or bearing stress.